Motor-winding.



PATENTED JAN. 15, 1907;

N. ,0 S R E D N A X E L A W* u... R

MOTOR WINDING. APPLICATION FILED JULY 23, 19'03.

TSHEETPSHEET 1.

A I MIM.-- :Bimvmnv Uw 1 MWL 513| lnven-ton ErnstFM/,Hlexandersb 511W. ALEXANDERSON. MoroR WINDING APPL'IOATIOH P ILED JULYZS, 1903.

v SHEETS-'SHEET 4.

Iventor. Ernst fwlexa'nderson.

' y tify.

E. BLW. 'A LEXANDER'SON.

VNo. 841,609.V

APP-L IOATION IILE) JULY 23, 1903.

Witnesses;

Nq. 841,609. PATENTED JAN. 15, 1907.-

E. F. W. ALEXANDERSO *Witne' Inventor:

ffl, )VQ- AEmst FvN/lexanderson @1W www No. 841,609. Y y P-ATBNTED JAN.=15,1907.

' E. P.' W. ALEXANDERSON.

MOTOR WWINDING.

APPLICATION FILED JULYZS, 1903 'l SHEETS-SERT 7.

Inventor. V ErnatFWHlaxar'ldrson WM ALL y.

l Witnesses:

y *MA1-4M,

UNITED STATES PATENT orrron ERNST F. WJ ALEXANDERSON, OF SOHENEOTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

MOTOR-WINDING.

' Patented Jan. 15, 190'?.

'Application filed July 23,1903.r Serial No. 166.676.

T0 all wiz/0791, it 1mi/,y concern:

Be it known that I, ERNST F. W. ALEX- ANDERsoN, a subject of the King of Sweden, residing at Schenectady, county of Schenectady, State of New York, have invented certain new and useful improvements in Motor- ,Windinga of which the following is a specification. 'l

The invention constituting the subjectmatter of the present applicationI relates to alternating-current motors provided withdrum-windings having their conductors so arranged and connected that by simply varyino` the coupling ot the sanie the number of poles `and consequently the speed of rotation:

e 12,151 of 1890 and'United States Patent No.

606,407, granted June 28, 1898, to Dobbie,

disclose means for doing this; butin both of these cases the large number of leads necessary renders the arrangement more or less objectionable. It is apparent that inlike manner the conductors ot a drum-Winding might also be provided with individual leads connecting with one or more controllingswitches which could be manipulated to give the desired pole numbers; but such an arrangement would be open to the same objection'. In order to overcome this objection, special windings have been proposed, among which may be mentioned those described in the 'following patents, which show 'special forms of drum-windings: Patent N o. 771,246, granted to. Henshaw October 4, 1004, which shows-a two-phase motor provided with a Winding arranged for two speeds in the y ratio o1` two to one, Patent No. 725,415, vgranted April 14, l903,to Dahlander and -Lindstrom, whichshows aV threehase motor having two s eeds in the ratio o two to one,

'and Patent-fo`.v 606,056, granted June 2l,

motor having two speeds in the ratio of three to one. nothing more has been attempted than to produce particular machines having particular speed ratios, and nothing in the nature of a generic type of winding broadly and' generally applicable tomultispeed motors for many different pole-numbers has been set out. On the other hand, I have not only invented a specific machine, but have also devised a species of winding which is capable of general application and which provides for any desired speed ratio with current of any number of phases.

. if we consider any drum-windin with reference to the direction of currentow in the several conductors, it will be apparent that at any given instant the current-'HOW in one half of the conductors will be in one direction and in the other half in the opposite directionthat is, in those portions 'of the conduc- In each of these cases, however,

the direction of current-how ineach conducy sidered, it will be seen that in certain conductors the direction of current-flow may be considered as the same for all the speeds, while in others the same vchanges in direction of current-flow take place in assing from one speed to another throng out all the speeds, considered in the-same order. It then follows that those conductors in which the direction of current-flow is the same for all the speeds may be connected together into one circuit, while other circuits may be made up of those conductors in Which the same changes in direction of current-flow take place in passingrom one speed to another throughout allthe speeds, as above indicated. These circuits or groups, as I have termed them, may then be connected are therefore-to be connected in one group, as described above, I pair ott the conductors, choosing for all the pairs conductors that are displaced by an equal number of slots, and connect each pair of conductors directly in series to form a coil or one turn of a coil. All the coils are thus equal in width,

' and the winding arranged in accordance with my invention is composed of uniform or counterpartcoils. vAnother point must be bornein mind in selecting pairs of conductors to connect in coils, and that is the number of speeds and the speed ratios desired. If the several coils are formed by connecting adjacent conductors of a group together so as to form the usual winding composed of a series of coils distinct Jr'roln each other and not overlapping, only one speed ratio two to one can be obtained. It is this connection that is employed in Patent No. 7 25,415, above referred to. By means of this connection uniform coils are obtained, which is not the case with the arrangement of Patent No. 606,056, also referred to above; but the arran ement of Patent. No. 725,415 can give o y two speeds, and those in the ratio of two to one.- That this is true is evident from thefollowing considerations; It two adjacent con ductors of a phase are connected in the samerJ coil, the relative direction of current-flow in the conductors is iiXed. The only variation that can be obtained consequently con sists in reversing alternate coils. I 'This reversall of alternate coils-is the control employed in Patent No. 725,415 and ives the only speed ratios ,attainable witht e Winding. shown. In order to get a greater number of speeds or a dierent speed ratio, it is essential that the direction of current in a conductor should be reversible relatively to the current in the conductors on each side of it, or, in other words, at least three adjacent conductors must be connected in independent coils. To accomplish this, while at the same time retaining uniform coils, I have devised a winding in which each coil is overlapped by at least one similar coil on each side. This gives an arrangement for each phase which resembles the usual polyphase winding, and on account of the overlapping or int-erlinking may aptly be termed a chain winding. I/Vhere each coil is overlapped by one coil on each side, four adjacent conductors are in independent coils, and by .properly reversing the'direction ofcircuit-flow through the several conductors the speedwratios of one totwo to three to four may be obtained. .Byletting each coil Abe overlapped by more than one coil on each side more than four adjacent conductors. may be connected in diii'erent coils and other speed ratios may be obtained.

My invention consequently consists in a novel Winding for alternating-current mo- .tors in which the winding or each phase of the winding for a polyphase motor consists of a plurality of uniform overlapping coils with means for varying the relative directions of current-flow in 'the coils. More speciiically considered, my invention conbility in arranging the winding for different pole-numbers, it is often desirable to be able to use any slot for any phase. p The standard Winding ordinarily-employed in alternatingcurrent motors is arranged withl two coils in.

each slot, and these two coils may obviously be of the same or of different phases; but such a winding does not su'lrice togive the complete `*distribution of each phase of a three-phase, motor that maysometimes be desirable. l

One feature of my invention consists in arranginttliree coils in each slot and con- C necting thetliree coils in different phases to formv Aa completely distributed three phase winding.

My invention further embraces certain novel connections of the groups or circuits above referred to, by which three and four speeds in a three-phase motor are obtained with -a maximum of four and ten leads per phase, respectively.

Other'ieatures and advantages of my invention will be apparent from the following description, taken in connection with the accompanying drawings, which illustratel the primary winding of a tour-speed three-phase motor constructed and arranged to be couy pledso as to give six, eight, twelve, and' twenty-four poles, and thereby speeds proportional to one, two, three, and four.

In said drawings, Figure 1 is a diagram of the complete three-phase windingaand con-y nections of the primary member vof said four. speed motor. Figs. 2, 3, and 4 are similardiagrains of the irst, second, and thirdpliase 'windings which are shown assembled in Fig. 1. Fig. 5 is adiagramsimilar to Fig. l, showing substantially the same windings provided with three-speed connections, which may be coupled tov give sin, eight, and twelve poles, and consequently'speeds proportional to two, tliree, and Pour. Figs. 6, 7,: and 8 are diagrams siniiiar to Figs. 2, 3, and 4,illus trating tlic iii'st, second, and Atl ii'd phase windings andconi'icctions,respectively,wiicn v i are sliown assembled in Fig. 5. Figs.` 9, .l(), and l l are diagrams ol' the conductors ol' the iirst, second, and tiird phase windings, respectively, in wl ich are illustrated the-relative directions of instantaneous current-How nec- IOO IIO

- respectively.

essary to produce six, I eight, twelve, and l 2 and 6 that set including the coils which extWenty-four poles. Fig. 12 is a simpliiied diagram of t-he windings and connections illustrated in Fig. 1 and indicates one way oi connecting up the various groups into which the different phase-windings are divided so as to obtain four speeds. Figs. 13, 14, 15, and 16 are diagrams illustrating the relative direction of current-flow in the different groups into which each phase-winding is divided by which the four pole-numbers, six, eight, twelve, and twenty-four, respectively, are obtained. Fig. 17 is a diagram similar to Fig. 12, illustrating the manner of connecting the dilerent groups of each phase-winding for the three pole-numbers, six, eight, and twelve; and Figs. 18, 19, and 20 are diagrams corresponding to Figs. 13 to 16, inclusive, illustrating the relative direction of current-How in the. different groups of each phase-winding by which the three pole numbers, six, eight, and twelve, respectively, are

obtained.

` In the accompanying drawings the magnetic core, which is shown developed upon a plane surface, is provided with seventy-two slots, which are indicated in the various figures by the rows of numerals above the windings, and in Figs. 1 and 5 the teeth ofthe core ,are'indicated by a row of vertical lines. The windings of the three phases are arranged on the core so that in each slot there is one conductor otl each phase, and these conductors are arranged one above the other in that order which will give equal reactances in the different phase-windings, the relative arrangement being shown in Figs. 1 and 5, where the conductor on the left is the uppermost conductor and that on the right the lowermost. For example, in slot 2 the conductor of the third-phase winding, which is shown in dot-and-dash lines, beinglocated at the right, occupies the lowermost position in the slot, while the conductor of theirstphase winding (indicated by full lines) occupies the uppermost position. Throughout the drawings the first-phase winding is shown in full lines and the second and third phase windings in dotted and dot-and-dash lines,

Placing three coils in each slot and connecting them in different phases gives the most complete distribution possible of`each phase, and consequently the maximum flexibility in connecting the winding properly for different numbers of poles.

The arrangement of the different phasewindings which go to make up the complete primary winding is best illustrated in Figs.

2, 3, 4, 6, 7, and 8, and each winding may e generally described as consisting of a number of sets of coils which are so disposed upon the vcore that each set embraces the left-handA conductors. of the set upon its right and the right-hand conductors of the set upon its le t.

l For example, if We consider inFigsm tend up through slots 4, 5, and 6 and downthrough slots 13, 14, and 15, respectively,

it will be seen that between the conductors in the slots 6 and 13 are located the conductors 7, 8, and 9, which are the right-hand conductors of the set of coils which extends toward the left, and conductors 10, 11, and 12, which'are the left-hand conductors ot a set of coils which extends toward the right. This vchain-like arrangement of sets of coils extends through the winding of each phase, and by means of it l am able to obtain the necessary pole-numbers by varying the connections of the coils. y

By connecting up the three-phase windings so that the directions of current-flow in the various conductors at any assunied instant will be as indicated by the arrows in Figs., 9, 10, and 11, six, eight, twelve, and twenty-four poles per phase may be obtained. Of these figures, Fig. 9 Ashows the necessary directions of current-flow by which thesepole-numbers may be obtained in the iirst-phase winding, Fig. 10 the second, and Fig. 11 the third, and in each igure the first row of arrows indicates the directions which give six cles; the second row, eight; the third, twe ve, and the fourth, twenty-four. "It will be noted by the above arrangement that a proper rotating iield is' obtained, the poles produced by the secondphase winding being displaced one-third the polar pitch from the corresponding poles produced by the iirstwinding and the poles produced by the {first-phase winding being displaced'one-third the polar pitch from those produced by the second-phase winding. This is clearly indicated for the six oles in Fig. 5, Wh'erethe letters N and indicate the `centers of north and southpoles, respectively, and the exponents 1, 2, and 3 indicate the particular phase-winding which is instrumental in' producing the vparticular pole and the subscript 6 the number of poles per phase.

In a winding arranged in accord ance with IOO IIO

my invention, so as toy give the requisite dirent-flow exists through vall the'changes of coupling. Considering the diagrams in Figs. 9, 10, and 11, if it is'desired to connectup the conductors of the winding so.-asito give six, eight, twelve, and' twenty-four poles per phasethe conductors of veach hase may be 'separated int'o groups, as fol ows: rst, all

those conductors in'which .the;direction of current-flow is the san; e for all the-pole-numbers; second, all those in which thediretion of current-How isthe same-ortwentyf-four poles and the opposite for six, eight, and twelve; third, all those conductors in which the direction of current-flow is the sarne for six and eight and the opposite for twelve and twenty-four; fourth, 'all those in which the direction of current-fiow is in one direction for twelve poles and opposite for six, eight, and twenty-four fifth, those in which it is in one direction for six poles and opposite for eight, twelve, and twenty-four; sixth, those in which it is in one direction for six and twenty-four and opposite for eight and twelve; seventh, those in which it is in one direction for eight poles and opposite for six,

twelve, and twenty-four, and, eighth, those in which it is in one direction for six and twelve poles and o pbsite for eight and twenty-four. Consi ering each of the phasewindings separately, in the caselof the firstphase winding the irst of the aforesaid groups includes those conductors in slots 4, 5, 6, 13, 14, 15, 52, 53, 54, 61, 62, and 63,616 second, those in slots 10,A 11, 12, 19, 20, and 21; the third, those in slots 1, 2, 3, 64, 65, and 66; the fourth, those in slots 7, 8, 9, 22,23,

24, 31, 32, 33, 70, 71, and 72; the fifth, those in Slots 16, 17, 1s, 25, 26, 27, 4o, 41, 4,2, 49, 50, and 51; the sixth, those in slots 46, 47, 48, 55, 56, and 57 the seventh, those in slots 28, 29, 30, 37, 38, and 39, and the eighth those in slots 34, 35, 36, 43, 44, 45, 53, 59, 60, 67, 68, and 69. Sii-nilarly for4 the second-phase winding the first group includes those' conductors in slots '1, 14, 15, 16, 23, 24, 25, and 64; the second, those in slots 8, 9, 17, 18, 56, 57, 58, 65, 66, and 67; the third, those in slots 2, 3, 4, 11, 12,13, 26, 27, 35, and 36; the

fourth, those in slots 5, 6, 7, 46, 55,68, 69, and the fifth, those in slots 28, 37, 50, 51, 52, 59,60, and 61; the sixth, those in slots 20,21, 22,29, 3o, 31, 44, 45, 53, and 54, theV seventh, those in slots 38, 39, 4 0, 47, 48, 49, 62, 63, 71, and 72,' the eighth, those in slots 19,' 19, 32, 33, 34, 41, 42, and 43. In a similar manner the conductors of the thirdphase winding may be divided'intoy correspondinggroups, as follows: the iirst group including those conductors in slots 6, 7, 8, 15, 16,.1730, and'39; the second, those in slots 1, 2, 9, 10, 11, 49, 5o, 53, 59, and 72; the third, those in slots 4,5, 18,' 19,20, 27, 28, 29, 67, and 68 the fourth, those in slots 12, 21, 60, 61,-62, 69, 70, and 71; the fifth, those in slots 3,` 42, 43, 44, 51, 52, 5 3,`and 66; the sixth, those in slots 13, 14, 22, 23, 36, 37, 38, 45,46. and 47 the seventh, those in slots 31, 32, 40, 41, 54, 55, 56,63, 64, end-.65,5116 the eighth those inslots 24, 25, 26, 33, 34, 35, 48,

, and 57. A'When the conductors of each phase winding are thusseparated into groups, the conductors of each group are connected together. These connected groups are designated by the letters A, B, C, D,.\E, F, G, and H, with exponents 1,H 2, and 3" to indicate the phase-winding ofwhich each particular groups form a part, the first of the above groups being designated A, the second B, and so on through the eight groups. In the case of group A', which is the first group of .the first-phase winding and which includes the conductors in slots 4, 5, 6, 13, 14, 15, 52, 53, 54, 61, 62, and 63, the coiiduotors are connected together in the order illustrated in `Fig. 2. The path forined byI this connection may be traced'as follows: Beginning with peint 24 it extends up through slot 15, down through 6, up through 14, down through 5, up through 13, down through 4, thence up through 63, down through 54, up through 62, down through 53, up through 61, down through 52, to the point 23. it should be noted at this point that this particular connection of the conductors is not essential, but that they might be connected in any other desired order, providing only that when connected the direction of current-flow at any assumed instant shall be down through slots 4, 5, 6,

y52, 53, .and 54 and upr through slots 13, 14,

15, 61, 62, and 63. ln a similar manner the other groups of the first-phase winding and all the groups of the second and third phase windings may be traced. Continuing with the group of the first-phase winding, group B/ extends between points 29 and 30, group C. between points 28v and 29, group D between points 24 and 25, group E between points 22 and 31, group F between points 25 and 26, group G between points 26 and 27 group H between, points 30 and31. case of the second-phase winding group A2 extends between points 33 and 34, B2 between points 39 and 40, C2 between points 38 and 39, D2 between points34 and 35, E2 be-` tween points 32 and 41, F2 between points35' and 36, G2 between points 36 and 37, H2 between points 40` and 41. third-phase winding group A2 extends between points 4 3 and 44, B2 between point-s 49 and 50,()a between points48 and 49, D3 between 51,1f2 between points 45 and 46,l G2 between @points 46 and 47, Hs between points 50 and 51.

Having formed the above groups, it then remains. to connect them to sornesuitable controlling-switch to give the proper change in direction of current-flow in the different oups for the different speeds. This may e done 'in any ease by connecting the lternunals of each group to a controlling-switch of a.typ`e shown in a patent to Bobbie, previously referred to, and one which may be readily designed for any given case but the present instance such a switch would-'necessitate sixteen leads per phase, and in order` to cut down this number of leads the coilsv are connected together in two branches each provided with end terminals and three intermediate terminals, -as clearly illustrated IOC Similarly, for the Fig. 12, and said terminals are connected by l suitable leads with a controlling-switchpro-$- vided with contact-segments arranged to give the directions of current-flow in the various groups indicated in Figs. 13, 14, 15, and 16. In these iigures the letters A, B, C, D,

E, F, G, and II are used to refer generally to the groups which in other figures are `provided with exponents to indicate the speciiic phase windings of which each forms a part. Similarly, the conductors of the windings may be grouped so as to vgive any number of speeds with a minimum number of leads. For example, the same winding which I have described above may be provided with connections for three speeds, and in such case only four leads per phase are necessary. If, for instance, the pole-numbers 6, 8, and 12 be selected, the steps will be as follows: Considering only the iirst three rows of Figs. 9, 10, and 11, since the twenty-four-pole connection is not wanted, four groups (designated generally by the letters I, J, K, and L) will be obtained. The iirst group I of each phase winding will comprise all those conductors in which the direction of Aciurent-iiow is the same for all pole-numbers; the second, J, ,those lin which the direction of current-How is in one direction for twelve poles and opposite for six and eight poles; the third, K, those in which it is in one direction for eight poles and opposite for six and twelve poles, and the fourth, L, those in which it is in one directi'on for six poles and opposite for eight Aand twelve poles.-

Considering now the lgroups of the first phase, the first group- I comprises the con- -ductors in slots 4, 5, 6,10, 11, 12, 13, 14, 15, -.19, 20,21, 52, 53, 54, 61, 62, 5nd 63, the s55- ond group, J, those conductors in slots l, 2, 3, 7, 3 9, 22, 23, 24, 31, 32, 33, 64, 65, 66, 70, 40771, and 72; the third group, K', those con- 4' ductors in `slots 28, 29, 30, 34, 35, 36, 37, 38, 39, 43, 44,45, 53,59, 60, 67, 63, and 69, and the fourth group, L, those in slots 16, 17, 18, `25, 26, 27, 40,41, 42, 46, 47, 43, 49, 5c, 51,-

"55, 56, and 57. In a similar` manner groups I2 J2 K2 L2 and Ia "J3 K3 KSL3 are` formed for the second and third phase windings, respectively. When the conductors of each phase winding are t us separated in groups, the conductors of ea h group are connected together as in the previous case, and, as there ointed out, the connections for any particuar group may be made in various ways but I have preferred to connect them up as illustra'ted in Figs. 6, 7 and 8. If we consider one of these groups, as group I', it will be seen that it extends between the 'points 10 and 11 throughout the various slots as follows: up through 15, down through 6, up

down throu`gh 4, thence up through 10, down through 19, up through 11, down through 20, up through 12, down through 21, thence up through 63, down through 54, up

through 14, down through 5, up through 6 5 through 62, down through 53, up through 61,

and down through 52, thence to point 11. In a similar manner the other groups of the first-phase winding may-be traced as follows: the group K between points pi and 13, L between points 12 and 13, J between points 10 and 12. In the case of the second-phase winding the group I2 may be traced between the points 14 and 15, J 2 between the points 14 and 16, K2 between the points 15 and 17, L2 between the points 16 and 17, and in the case of the third phase winding group I3 may be traced between the points 18 and 19, J3 between the points 18 and 20, K3 between the points 19 and 21, and L3 between the points 20 and 21. Having arranged the grou s of the windings for the three-pole num ers, it only remains, as before, vto connect them together in such a manner that the necessary changes in direction of currentiiow may be obtained by suitable changes in the coupling, and, as before pointed out, this may be accomplished by providing each group with two terminals and connecting all of said terminals to a suitable controller. In the present instance, however, the necessary changes may also be obtained and with fewer leads byconnecting the groups of each phase winding in a closed circuit, as indicated in Figs. 17, 18, 19, and 20, and connecting the points between the groups of each phase to a controller S3.

Referring again to the four-speed connections, as shown in Figs. 12 to 16 inclusive, the groups of each phase winding are arranged in two branches each of which is provided with two end terminals and three intermediate terminals. Of the two branches of the iirs'tphase Winding one branch includes the groups E H B C and the other Ithe groups A D F G, the former being provided with end terminals 22 and 28 and intermediate terminals 29, 30, and 31 and the latter with end terminals 23 and 27 and intermediate terminals 24, 25, and 26. Similarly, the groups of the second-phase winding are connected so as to form two branches, one of which includes E2 H2 B2 C2 and the other the groups A2 D2 F2 G2, the former being provided with end terminals 32 and 38 and intermediate terminals 39, 40, and 41 and the latter with end terminals 33 and 37 and intermediate terminals 34, 35, and 36. The third-phase winding is also divided into two branches, one of which includes the groups E3 Hs B3 C3 and the other the groups A2 D3 F3 G3, the former being provided with terminals 42, 48, 49, 50, and 51 and the latter with terminals 43, 44, 45,- 46, and 47. All of these terminals are electrically connected to the xed fingers of a controller S4, each of the fingers being desig- 1 z 5 nated by the same numeral as the corresponding terminal, but being provided with an exponent a. The rotatable member of the controller S4 is provided with suitable segments which coperate with said iixed fingers 1,30

IOO

lss

to produce the necessary changes in coupling. It is also provided with segments R2 S2 T3, which are adapted to engage the contact-iingers R' S' T', which are connected by suitable leads to supply-mains It, S, and T, res ectively, extending from a suit-able three-p iase twenty-tour poles in the winding, the rotatable member of the controller is moved unt-il the contact-segments in the line 24 24 are brought into engagement with the contactiingers. In this position of the controller a Y connection is made, the three branches extending i'roni the three supply-mains being traced as follows:l One of' these extends from the supply-main R to contact-iinger R', thence tln'ough contact-segments R3, 221), contact-finger 223L to terminal 22, groups E' H' B' C' to terminal 2S, contact-{inger 2S, contact-segments 28b 273, contact-iinger 273, terminal 27, groups F' D' A' terminal 23, contact-iingcr 23, contact-segment 23h to the neutral point 52. A second-,branch extends from the supply-main S to'coi'i'tact-iinger S', thence through contact-segments S2 33b 333, groups A2 D3 F2 G3, terminal 37, contact-finger 373, contact-segment@ 37b 3,83, contact-iinger 333, terminalSS, groups Cil/B2 H3 E3, terminal 32, contact-finger 32;/eontact-segment 32b to neutral point 2.,/A third branch extends from 'the supply-main 'l/ to contact-iinger T', thence through contactsegments T2 42h, contact-finger 42, terminal 42, groups E3 H3 B3 C3, terminal 4S, contactfinger 483, contact-segmentsN43b 47 b, contactfinger 473, terminal 47, groups G3 F3 D A3, terminal 43, contact-iingcr 433, contact-segment 43b to neutral point 52. With this'position of the controller it will be seen that the direction of current-How through each ofthe phase-windings will be that indicated by Fig. 16 and that pole-centers will be produced for the three phases, as indicated by the characters N' ,4 SQ,4 in Fig. 2, N324 S32, in Fig. 3, and N324 S324 in Fig. 4. Similarly, if the controller is moved so that the contact-segments in the Iline 12 12 are brought into engagement with the contact-fingers a Y connection will also be Jformed whose three branches may be traced as follows z One branch, beginning with the supply-main R, extends to the contactiinger R', thence through contact-segments R2 29, contact-linger 293 to terminal 29 between groups C' and B', there dividing, assing through one branch, including groups H', to the terminal 31 and another, in-

cluding groups C', terminal 28, contact-1inment 24, contact-nger 243 to terminal 24 between the groups A D', there-dividing and passing through tWo branches to the point 26, one including the groups D F' and the other including group A', terminal 23, cont act-finger 233, contact-segment 27, contact-lnger 273, terminal 27, and group G', thence to the contact-nger 263, contact-segment 26c to neutral point 53.- A second branch extends from the supply-main S to contact-finger S', thenceVA through contact-segment S3, contact-segment group E3, terminal 42, contact-iinger 423,

contact-segments 42C 43C, contact-finger 483, terminal 48, and group C3, to terminal 49" thence to contact-iinger 493, contact-segment 49C to neutral point 53. A third branch eX- tends from the supply-main T to contact-iinger T', thence through contact-segments T3 39', contact-iinger 39'1 to terminal 39 between the groups B2 and C3 of the secondphase windmgs, there dividing and passing through one branch, including groups H3, to the terminal 41, and through another, including group C3, terminal 38, contact-iinger 333, contact-segments 38.3 323,'y contactiinger 323, terminal 32, and g1oup,`E3,to erniinal 41, thence through contact-iingcr `4,1, contact-segment 34", contact-linger 343l lo terminal 34 between the groups A2 and D3 of the second-phase winding, there dividing, passing through one branch, including groups D2 and F3, to terminal 36 and through a branch, including group A3, terminal 33, contact-finger 33, contact-segment 37C, contactfinger 37, terminal 37, group G3, to point 36, thence to contact-finger 363, contact-segment 36c to neutral point 53. This position of the controller then gives the directions of currentilow indicated by Fig. 15 ail/d produces pole- ICO centers `for the first, second, and third phase windings, as indicated in Figs. 2, 3, and 4, re-

spectively, b the characters N',. S',` NZH, S22, N312, an S312. In a similar manner the circuits may be traced for the eight and six pole positions of the coiitgoller, which would give the directions of current-How indicated by Figs. 14 and 13, respectively, and produce pole-centers for the first, second, and third phasewindings, as indicated in Figs. 2, 3, and 4, respectivelg, by the characters NB, S'S

N38, S38, N38, and 8, which show the centers of eight poles, and No, SG, N26, S26, N36, and

S36, which show the centers of six poles, the former corresponding to Fig. 14 and the latter to Fig. 1'3.

Where the machine is designed tor the three speeds in which the pole-numbers 6, 8, and 12 are used, the connections are much simplified, as clearly indicated in Fig. 17 and, as previously stated, only four leads per phase are necessary to produce the changes in coupling. In this arrangement the groups of each phase-winding are.`connected together so as to form a closed circuit,'and suitable leads are carried out from terminals between the said groups. For example, in the case of the iirst-phase winding the groups I J K L are connected together into a closed circuit provided with terminals 410, 11, 12, and 13, from which suitable leads extend tothe controller. ner leads extend Ifrom theterminals 14, 15,

16, 17, 18, 19, 20, and 21, Each of these leads vconnects with a contact iinger of a suitable controller S3, and the iingers are designated with the same numerals as the corresponding terminals in the winding with which they connect, but are provided in each inst-ancewith anexponent a Therotatable member of the'controller S3 is provided with suitable contact-segments for engagement with thesecontactiingers, so arranged as to give the necessary changes .in the coupling of the diiierent groups. Contact-segments Rb, Sl?, and Tb are also provided land are adapted to cooperate -with contact-fingers Ra, S, and T,`which are connected with mains R, S,and T, respectively, which lead from a suitable three-phase source of supply. The three positions of the controller are indicated by the linesS 8,12 12, and 6 6, and when the contacts through which these lines extend lare in engagement with the contactfingers the couplin is such as to give eight, twelve, and six po es, respectively. It the controller be moved so as to give eight poles in the Winding, the contact-segments in the p line S 8 engage the contact-fingers and a delta connection is made. One branch of this connection extends from the supply-main R to the'contact-iinger Ra, thence through contact-segments Rb 10b, contact-rhiger 10, terminal 10, thence to terminal 13 through two branches, one of which includes groups Il L', ,the other I K', thence tlu'ough contact-fingers 13a, contact-segments `13b Tb,

-'-contact-inger 'Ia to supply-main T. The

second extends from supply-main l, contact-finger R, contact-segments- Rb 17h,l

contact-iinger 17a to terminal 17, thence to terminal 14 through two branches, one oi which includes groups L2 J2 and the other K2 I2, thence to contact-finger 14a, contactsegments 141) Sb, contact-iingcr S to main S.- The third branch extends from the main S to contact-ringer S, thence through con- In a similar mantact-segments Sb and 2lb, contact-finger 21a to terminal 21, thence to terminal 18 through two branches, one of which includes groups L3'J`3 and the other K3 I3, thence to contactfinger 18a, contact-segments 18b and Tb, contact-iinger Ta to supply-main T. The connection provided by this position of the controller gives the ldirection of current-How in the several groups indicated in Fig. 19 and produces pole-centers as indicated by the characters NS, S48, N28, S28, N38, and S3,s in Figs. 2, 3, 4, 6, 7, and 8.

In a similai` manner the circuits may be traced for the six and twelve pole positions oi the cont-roller, and the directions of current-flow in the several groups will be that indicated in Figs. 18 and 20, respectively, and 'pole-centers will be produced as indicated by the characters Na, S, N26, S26, N36, S387 Nizy S/12y`N2125 S2121 N312: and S312 in Figs' 2, 3, 4, 6, 7, and8.`

I do not wish my invention to be' limited to windings which are made up of coils of a single coil might take the place of a se't ci coils, so that where I use the expression set ofcoils it is intended to cover one or more coils. Furthermore, instead oi' each slot containing one conductor ot cach phase winding the conductors may be arranged in separate slots or otherwise so long as they are associated so as to have the same etl'ect, and in order to bring out this fact in the claims I have used the expression corresponding portion of the `core, by which I niean that portion in which are located the conductors of the diiierent phase windings which are associated so as to produce the saine eiiect as if they were in the same slot. It is therefore clear that many modiiications and alterations may be made without departing from the spirit o'f my invention, and I aim to cover. by the terms of the appended claims all such modifications and alterations.

VVha-t I claim as new and desire to secure by Letters Patent of the United States,is-

1. A phase-winding for a multispeed alternating-current motor, having its conductors connected so-as to form a pluralityot groups in a plurality of which the direction of current-iiow is the same for a plurality of speeds of the motor, and means for 'changing the relative connections ot' the several groups for the different speeds.

2. A winding for a multispeed alternatingcurrent motor, having its conductors connected so as to form a plurality of groups in each of which the direction of current-flow is ICC the same for a plurality of speeds ot the imo V tor, and means for changing the relative cone-, 1 f

Y each other and With said terminals that by i Ychanges oit the coupling of said terminals th`e g een,

nections of the several entspeeds.

A Winding for a multispeed alternating current motor,` having its conductors connected so as to form a plurality of groups in each of which the direction of current-HOW is the same for a plurality of speeds of the motor and in sonie oi Which the current-How is the sameior the remaining speeds and in some of which it is reversed for the remaining speeds, and means for changing the relative connections oi the groups for the diiiierent speeds.

4. A winding for a multispeed alternatingcurrent motor, having its conductors connected so as to form three or more groups in one of Which the direction of current-lion' is the same for all speeds of' the motor and in others of which the direction of current-flow is the same for some of the speeds and reversed for the remaining speeds, and means for changing the relative cdimections oi the several groups for the dii'eient speeds.

5. A windin g for a multispeed alternatingcurrent motor, `which consists oi' a plurality of sets of coils, each'of which sets overlaps the adjoining set on either side so as to pro duce a chain-like arrangement of such sets, the conductors of said coils being connected so as to form a plurality oi' groups, and means for changing the relative connections of said groups for the diil'erent motor speeds.

6. In a multispeed alternating-current motor, the combination ot' a toothed or slotted core and a polyphase-win ding thereon consisting of a distinct winding for each phase, each phase-Winding consisting of a plurality of sets of coils each of which overlaps the adjoining setron either side so as to produce a chain-like arrangement of such sets, said phase-windings being so arranged that each slot or each corresponding portion of the core carries the saine number of conductors of each phase-Winding, leads extending-from said windings. and means Jfor changing the relativo connections of said leads for the diiierent motor speeds.

7. A multispeed alternating-curreiit motor provided with primary drum-windings having their conductors connected together in groups and provided with terminals, the conductors of said windings being so associated with each other and said terminals that by changes of' the coupling of said terminals the number of poles may be Changed so as to give four speeds, and means for changing sai d coupling.

8. A multispeed alternating-current motor provided with primary drum-windings having their conductors connected in groups and provided with terminals, the conductors' of said windings being so associated with groups for the diiferpole-numbers N, N /2, N /3 and N /4 are obl tained, and means for changing said couplin 9g. A multispeed alternating-current motor provided with primary drum-windings having their conductors connected in groups and provided with terminals, the conductors of said windings being so associated with each other and with said terminals that by changes of the coupling of said terminals the pole-numbers N, N/ 2 and N 3 are obtained, and means for changing the coupling.

10. A multispeed alternating-current motor provided with primary drum-windings having their conductors connected in groups and provided With terminals, the conductors of said Windings'being so associated with each other and with said terminals that by changes of the coupling of said terminals the pole-numbers N, N/Z and N/4 are obtained,

and means for changing said coupling.

11. A multispeed alternating-curren motor provided with primary 'drum-windings having their conductors connected in groups and provided with terminals, the conductors of said windings being so associated with each other and With said terminals that by changes of the coupling of said terminals the pole-numbers N, N /3 and N /4 are obtained, and means for changing said coupling.

12. Aniultisp'eed alternating-current motor provided with primary drum-windingshaving their conductors connected in groups and provided with terminals, the conductors of said windings being so associated with each otherl and with said terminalsvthat by changes of the coupling of said terminals the pole-numbers N /2, N 3 and N /4 are obtained,

and means for changing said coupling.

13. A multispeed alternating-current motor provided with primaryr drum-windings having their conductors connected in groups and provided with terminals, the conductors of said windings being so associated witheach other and with said terminals that 'by changes of the coupling of said terminals 'the pole-numbers N 2 and N 3 are obtained, and means for changing said coupling. 'A

IIO

14. A multispeed alternating-current motor provided with primary drum-windings having their conductors connected in groups and provided with terminals, the conductors of said windings being. so associated with each other and with said terminals that by changes of the coupling of said terminals the pole-numbers N 2 and `N/4 are obtained, and means for changing said coupling.

15. A multis'peed alternating-current Ino- I tor provided With primary drum-windings having their conductors connected in groups and provided with terminals, the conductors of' said windings being so associated with each l other and with said terminals that by changes of the coupling of said terminals the pdlenumbers N 3 and N /4 are obtained, and means for changing said coupling.

16. A two-speed alternatin -current motor provided with primary drum-windings having their conductors connected in groups and provided with terminals, the conductors of said windings being so associated with each other and with said terminals' that by changes of the coupling of said terminals the polenumbers N and N /4 are obtained, and means for changing said coupling.

17 .'-A two-speed three-phase alternatingcurrent motor provided with primary drumwindings having theirconductors connected in groups and provided with terminals, the conductors of said windings being so associated with each other and with said terminals that by-changes of the coupling of said terminals the pole-numbers N and N 3 are obtained, and means for changing said coupling.

18. A multispeed alternating-current motor, provided with primary drum-windings having their conductors connected so as to form a plurality of groups, said groups bein arranged in a plurality of branches providetgi ywith end terminals and a plurality ofintermediate terminals, and means for changing the connections of said terminals to vary the direction of current-flow in the dii''erent groups and thereby change the numberl of poles.

19. A multispeed alternating-cmrent inotor, provided with 'primary drum-windings having their conductors connected so as to forma plurality of groups, said groups being arranged in two branches provided with en d terminals and a plurality or' intermediate terminals, and means for changing the connections oi said terminals to vary the direction of current-now in the groups to change the number of poles.

20. A multispeed alternating-current motor, provided with primary drum-windings having their conductors connected so as to form ei ht groups, said groups being arranged in two ranchesjprovided with two end terminals and three intermediate terminals per' branch, and means for changing the connections of said terminals to vary the direction of current-flow in the groups and thereby change the number of poles.

21. A multispeed, three-phase alternatingcurrent motor, provided with primary drumwindings having their conductors connected together in groups and provided with a maximum of ten terminals per phase, the conductors of said windings being so associated with each other and with said terminals that by changes of the couplings of said terminals the number of poles will be changed so as to give four speeds, and means for changing said 22. A multispeed, three-phase alternatingcurrent motorprovidedwith primary drumwindings having their 4conductors connected together in groups and provided with a maximum of ten'terminals per phase, the conductors of said windings being so associated with each other and with said terminals that by changes ofthe couplings of said terminals the pole-numbers- N N/2, N/ 3 and N/4 are obtained, and means for changing said coup- 2g3. A multispeed, alternating-current motor, provided with primary drum-windings having their conductors connected together in groups and provided with terminals, the conductors of said 'windings being so associated with each other and with said terminals that by changes of the cou ling of said terminals the number of po es may be changed so as, to give three speeds, and means for changing said coupling.

24. A multispeed, three-phase alternatingcurrent motor provided with primary drumwindings having their conductors connected together in groups and provided with a maximum of'twelve terminals, the conductors of said. windings being so associated with each 'other .and with said terminalsv that by changes of the lcoupling of said terminals the number ofpoles will be changed so as to give three spee s, and means for changing said coupling.

25. A multispeed, three-phase alternatingcurrent, motor provided with primary drum- Windings havingl their4 conductors connected together in groups and provided with a maximum of twelve terminals, the conductors of said windings being so associated with each other and with said terminals that by changes of the coupling of said terminals the pole numbers N/2, N/S and N/-i are obtained, and means for changing said coupling.

26. A multispeed, three-phase alternatingcurrent motor having primary windings, the windings of each phase being divided into groups which are connected in a closed circuit, terminals in each of said circuits between said groups, the conductors of each phase of said windings being so associated with each other and with said terminals that by'changes of coupling of the said terminals l the number oi' poles of the motor may be changed so as to give three speeds.

27. A multispeed three-phase alternatingcurrent motor having primary windings, the winding of each phase being provided with .fourterminala the conductors of each phasewinding being so associated with each other and with lsaid terminals 'that by changes of the cou ling of said terminals theY number of poles o the motor may be changed so as to give three speeds.

28.- A winding for a three-speed alternating-current motor having lits conductors connected so as to form a plurality of groups, in

one of which the direction of current-How is the same for all speeds of the motorl and in AJA the others of which the direction of currentlow is the same for two speeds and reversed for the other speed, and means for changing the relative connections of the several groups for the different speeds.'

29. A phaseavinding for a multispeed alternating-current motor, which consists of a plurality of coils having their conductors connected so as to form a plurality of groups connected in a closed circuit, terminals located in said circuitat points between said groups, and switching means for changing the direction of current-ow through said groups.

30. A polyphase-winding for a multispeed alternating-current motor, consisting of a plurality of phase-windings each of which consists of a plurality of coils having their conductorsV connected so as to form a plurality of groups connected in a closed circuit,

` terminals located in said closed eircuits at points between said groups, and switching means for changing the direction of current- 'Winding having each phase formed of uniform overlapping coils connected in groups, and means for varying the connections of said groups.

32. In a multispeed-motor, a distributed winding having each phase formed of uniform overlapping coils, and means Vi'or varying the relative directions of current-How in said coils. Y

33. In a multispeed-motor, a distributed winding having each phase formed of uniform overlapping coils connected in groups, said groups being connected in a closed circuit, and means for varying the points of'conneetion Jrom said circuit to the source of current. A v l 341-: In a multispeed-motor, a distributed winding having each hase formed of uniform overlapping coi s connected in four groups/said groups being connected in series in a closed circuit, and means for varying the points of connection from said closed circuit to the source of current.'

35. In a multispeed-motor, a distributed Winding for each phase of themotor, each coil of said Winding being overlapped on each' side by a coil connected in the same phase.

36. In a multispeed-motor, a distributed winding for each phaseof the motor, [each coil of said winding being overlapped for onethird its width on each side by a coil connected in the same hase.

37. In a mu tispeed-motor, a slotted core, a winding arranged vwith three coils in each slot, said coils being connected in diil'erent phases to form a three-phase Winding and the coils of each phase being connected in groups, and means for varying the connections of the groups to produce different pole-numbers.

38. Ina multispeed-motor, a slotted core, a winding arranged with three coils in each slot, said coils Ibeing connected in different phases to form a tbree-phase winding and thel coils of each phase being connected in groups,

and means for connecting said groups forv different pole-numbers.

39. In a multispeed-niotor, a slotted core, a three-phase winding carried insaid slots, each phase being composed of uniform overlapping coils connected in groups and each slot containing three coils connected one -1n each pb ase, and means for varying the connections of the groups of each phase to -connect the Winding for different pole-numbers.

40. In a multispeed-motor, a slotted core, a three-phase winding carried in said slots, each phase being composed of uniform cdils connected in groups and each slot containing three coils connected one in each phase, and means for varying the connections of the groups of-eaeh ph ase.

41', A winding foramultispeed alternatingcurrent motor havin T the conductors of each phase connected in tiree or more groups, all the conductors in which the relative directions of current-How are the same' for all speeds of `tbe motor being connected in the saine `group so that the number .of poles of the motor may be varied by a simple change of coupling of the groups.

ing its 4conductors 'connected in a plurality of groups, said conductors being so arranged that by reversingjthe relative terminal eon.

ERNST F.. W. ALEX NDERSON.

INitnesses:

BENJAMIN B; HULL, HELEN ORFORD.

95 42. In a multispeed-motor, a winding havroo 

